Jack prop



May 29, 1923. I 1,457,145

5. 1.. BUCHANAN ET AL JACK PROP Filed July 1'7. 1922 A T TORNE Y.

Patented May 29, 1923.

STEPHEN L. BUCHANAN AND FRANK J. LYTroNjor GOEBURKTVIIRGIVEINIAIT 1'JACK rnor. w 7

Application filed July 17,

Toalllwhomz'tmay concern: A. Be itknown that we, STEPHEN L. BU- QHAANandFRANK J. LY'r'roN, citizens ofv the United States, residing atCoeburn, in the county of Vise and Stateof Virginia, have inventedcertain new and useful ,Improve-, ments in Jack Props, of which thefollowing. is a specification. M

This inventionrelates. to adjustable mine props, and has for one of itsobjects to provide a device of this character including a stock memberhavingrmeans forquickly increasing -its' length to correspond to theloca-- tion which it is to occupy and with additional and separate-meansfor imparting a powerful longitudinal strain to rigidly support thedevice in position.

Another object of the invention is to pro-. vide, a device of thischaracter including a stock member having means for quickly increasingits length tocorrespond to the location whichit is to occupy, and withadditional and separate means for. imparting a powerfullongitudinal'strain to rigidly'sup'-' port the device in position, andwith means for holding the stock in its adjusted position; With theseandother'objects in View the invention consists in certain novelfeatures of "construction as hereinafter shown and described and thenspecifically pointedout in the claims, and in the drawings illustrativeof the preferred embodimentof the invention:-

Figure 1 is a vertical elevation in section on the line 11 of Fig. 2.

Fig. 2 is a front elevation. Fig. 3 is a section. on the line 3-3 ofFig.4.

Fig. 4 is a transverse section on the line 4-4 of Fig. 2.

Fig. 5 is a sectional detail of the lower portion of the device.

In operating coal mines when the cutting niachineis tobe located at theface of the gallery or the like. the miner is required to place at leasttwo or more timbers ,or props under the roof as a precautionary measure,to insure the safety of the miner. The mining timbers thus employed arerather heavy and cumbersome and much time and labor is required to placethem in position and to move them from place to place.

The principal object of the present invention is to provide anadjustable device to be employed in place of the ordinary mine tim-1922. Serial m. 53,705.)! I

ber orv jack rops, be quickly adapted to galleries} or driftslj ofivarying heights, and which may be repeat-= edly used or;moved' fromplaceto placev as required and withoutdetachingany of the parts.

tubular supportingbody including a :rear portion10, spaced side portions.11 and- 12 back '10 and sides 11- and 12'to form a tubular guideway to'slidably receive a stock member'15."

At its upper end the stock is'pro The improved device comprises a hollowvided with a bearing head 16 and is' formed, with gear teeth 17 in oneside face and ratchetteeth 18 in another-side face; i .1

Formed in the inner face o-f-the side portion-:11 isan elongatedpocketor seat .19 .-to

receive a bar 20'having ratchet teeth 21 corresponding. to and adaptedtobe engaged by the ratchet teeth 18 of the stock 15 when in one positionas shown. in'Fig. :2; or-with-j drawn. from engagement with the teethof.

the stock when in in'Fig. 3.v

A; spring22 is disposedin the seat 19 and constantly-{engages thewbar 20to holdit another position, as shown yieldably in its extended positionwith its teeth 20in engagement with the teeth 18 of the stock and thushold the stockin adjusted position. i I I A; heavy wire fU-shaped loop23 engages the bar 20 1and"extends'through the side 11 of thes'upportand is coupled at 21 to an operatil'ig lever 25 "whereby thebar 20 maybe-movedi'bodily into its seat '19 against'the resistance of the spring22 and thus disconnect the teeth 21 of the bar from engagement with theteeth 18 of the stock and release the latter and permit it to fall bygravity into its lower position.

Extending through the sides 11 and 12 of the support is a shaft 26carrying a gear wheel 27 in constant engagement with the crank wheel 28externally of the'side member 12 to actuate the gear'wheeh and thusrapidly move the stock 15 upwardly. EX-

, tending through the sides 11 and 12 of the teeth 17' of the stock.andxprovided with a The short end of the lever 30 is formed into a gearsegment 32 adapted to engage the teeth 17 of the stock when the lever isin its inner position as shown in Fig. 1, and disconnected from theteethwhen in outer position as shown in Fig. 5.

By this arrangement a strong leverage force may be imparted upwardly tothe stock 15 a distance equal to the throw of the lever, the adjustedposition being held by the ratchet barQO until the lever can be releasedby drawing it outwardly the length of the slot 31 and again applied tothe stock. Thus a step by step movement of this stock may beaccomplished to apply a strong longitudinal strain to the device tofirmly hold it'in position.

Thus in applying the device the crankwheel 28 is actuated to rapidlymove the stock upwardly to correspond to the distance between thefloorand roof of the gallery, and the lever 30 then operated to forciblya'nchor the device in place.

When the stock is to be released it is only necessary to disconnect thelever 30'by drawingit outwardly, the length of its slot 31 and forcingthe lower end of the small lever 25 inwardly "to cause the withdrawal ofthe bar 20 and release the stock 15 which will then fall-by gravity intoits lower position.

The #device can then be removed for use in another location, or storedfor future use.

Attached to the face member 14 is a ring 33 to which'a pull cable may beattached if there be-dafnger of the roof falling. In that event' a cableis attached at one end to the ring 33 and the otherend to a mine car ata safe distance, the miner having withdrawn to a position of the minecar when out of the danger'line. The car is then started and theifmlproved prop pulled out from beneath the a ing roof without danger tothe opera tors.

The jack body on the sides 11 and 12 thereof, near the top or upperendof the same carries loop handles 34 which serve to permit the lifting ofthe jack in its entirety by hand when occasion requires. It is of courseunderstood that'these handles may be of any desirable type and arefastened in any manner to the body of the jack.

The improved device, which is technically called a jack prop, can beconstructed of any suitable material and of any .suitable size andstrength, and a number can be carried on the motors of the mining carsand used as an emergency prop or timber in any part of the mine.

The preferred embodiment of the invention is disclosed in thedmwings andset forth in the specification, but it will be understood thatmodifications within the scope of the claimed invention may be made inthe construction without departing from the principle of the inventionor sacrificing any of its advantages.

Having thus described the invention, what is claimed as new isz- 1. Amine prop comprising a tubular support, a stock provided with a bearinghead and movable in said support, said stock having gear teeth in oneface and ratchet teeth in another face, a bar movable in said supportand having ratchet teeth adapted to be engaged withthe ratchet teeth ofthe stock, an operating appliance carried by said sup port andengageable with the gear teeth of the stock, and means carriedby saidsupport for disengaging the bar from the stock. 2. A mine propcomprising a. tubular support, a stock provided with a bearing head andmovable in said support, said stock having gear teeth in one face andratchet teeth in another face, a bar movable in said support and havingratchet teeth adapted to be engaged with the ratchet teeth of the stock,a gear wheel mounted in the support and engageable with'the gears ofthestock and operating to quickly actuatethe stock, a lever pivoted in thesupport and having gear teeth engageable with the gear teeth of thestock whereby a powerful lifting force may beapplied' to the stock.

In testimony whereof,we affix our signatures hereto.

STEPHEN L. BUCHANAN. FRANK J. LYTTON.

